Location, time, and/or pressure determining devices, systems, and methods for deployment of lesion-excluding heart implants for treatment of cardiac heart failure and other disease states

ABSTRACT

Devices, systems, and methods for treating a heart of a patient may make use of structures which limit a size of a chamber of the heart, such as by deploying one or more tensile member to bring a wall of the heart and a septum of the heart into contact. A plurality of tension members may help exclude scar tissue and provide a more effective remaining ventricle chamber. The implant may be deployed during beating of the heart, often in a minimally invasive or less-invasive manner. Trauma to the tissues of the heart may be inhibited by selectively approximating tissues while a pressure within the heart is temporarily reduced. Three-dimensional implant locating devices and systems facilitate beneficial heart chamber volumetric shape remodeling.

CROSS-REFERENCES TO RELATED APPLICATIONS

The present application is related to that of U.S. patent applicationSer. No. 11/536,553, filed on Sep. 28, 2006; and to that of PCTapplication no. PCT/US06/32663, filed on Aug. 1, 2006; the disclosuresof which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

The present invention is generally directed to improved devices,systems, and methods for treatment of the heart. Exemplary embodimentsprovide implants and methods for alleviating congestive heart failureand other progressive diseases of the heart. Congestive heart failuremay, for example, be treated using one or more implants which areselectively positioned relative to a septum and wall of the heart so asto exclude scar tissue and limit a cross section across a ventricle.Trauma to the heart tissues may be inhibited by decreasing a size of theheart chamber and/or approximating tissues when stress on the tissues islimited. Implant locations and overall chamber remodeling achieved by aplurality of implants may be determined so as to provide a beneficialvolumetric chamber shape. Exemplary axially curved catheter bodies mayenhance measurements for and implant positioning control over suchremodeling.

Congestive heart failure (sometimes referred to as “CHF” or “heartfailure”) is a condition in which the heart does not pump enough bloodto the body's other organs. Congestive heart failure may in some casesresult from narrowing of the arteries that supply blood to the heartmuscle, high blood pressure, heart valve dysfunctions due to rheumaticfever or other causes, cardiomyopathy (a primary disease of the heartmuscle itself), congenital heart defects, infections of the hearttissues, and the like. However, in most cases congestive heart failuremay be triggered by a heart attack or myocardial infarction. Heartattacks can cause scar tissue that interferes with the heart muscle'shealthy function, and that scar tissue can progressively replace moreand more of the heart tissue. More specifically, the presence of thescar may lead to a compensatory neuro-hormonal response by theremaining, non-infarcted myocardium.

People with heart failure may have difficulty exerting themselves, oftenbecoming short of breath, tired, and the like. As blood flow out of theheart slows, blood returning to the heart through the vascular systemdecreases, causing congestion in the tissues. Edema or swelling mayoccur in the legs and ankles, as well as other parts of the body. Fluidmay also collect in the lungs, interfering with breathing (especiallywhen lying down). Congestive heart failure may also decrease the abilityof the kidneys to remove sodium and water, and the fluid buildup may besufficient to cause substantial weight gain. With progression of thedisease, this destructive sequence of events can cause the eventualfailure of the remaining functional heart muscle.

Treatments for congestive heart failure may involve rest, dietarychanges, and modified daily activities. Various drugs may also be usedto alleviate detrimental effects of congestive heart failure, such as byexpanding blood vessels, improving and/or increasing pumping of theremaining healthy heart tissue, increasing the elimination of wastefluids, and the like.

Surgical interventions have also been applied for treatment ofcongestive heart failure. If the heart failure is related to an abnormalheart valve, the valve may be surgically replaced or repaired.Techniques also exist for exclusion of the scar and volume reduction ofthe ventricle. These techniques may involve (for example) surgical leftventricular reconstruction, ventricular restoration, the Dor procedure,and the like. If the heart becomes sufficiently damaged, even moredrastic surgery may be considered. For example, a heart transplant maybe the most viable option for some patients. These surgical therapiescan be at least partially effective, but typically involve substantialpatient trauma. While people with mild or moderate congestive heartfailure may benefit from these known techniques to alleviate thesymptoms and/or slow the progression of the disease, less traumatictherapies which significantly increase the heart function and extendlife of congestive heart failure patients has remained a goal.

It has recently been proposed that an insert or implant be placed in theheart of patients with congestive heart failure so as to reduceventricular volume. With congestive heart failure, the left ventricleoften dilates or increases in size. This can result in a significantincrease in wall tension and stress. With disease progression, thevolume within the left ventricle gradually increases and blood flowgradually decreases, with scar tissue often taking up a greater andgreater portion of the ventricle wall. By implanting a device whichbrings opposed walls of the ventricle into contact with one another, aportion of the ventricle may be constricted or closed off. By reducingthe overall size of the ventricle, particularly by reducing the portionof the functioning ventricle chamber defined by scar tissue, the heartfunction may be significantly increased and the effects of diseaseprogression at least temporarily reversed, halted, and/or slowed.

An exemplary method and implant for closing off a lower portion of aheart ventricle is shown in FIG. 1, and is more fully described in U.S.Pat. No. 6,776,754, the full disclosure of which is incorporated hereinby reference. As illustrated in FIG. 1, a patient's heart 24 has beentreated by deployment of an implant across a lower portion of the leftventricle 32 between septum 28 and a left wall or myocardium region 34.The implant generally includes a tensile member which extends betweenanchors 36 and 38.

A variety of alternative implant structures and methods have also beenproposed for treatment of the heart. U.S. Pat. No. 6,059,715 is directedto a heart wall tension reduction apparatus. U.S. Pat. No. 6,162,168also describes a heart wall tension reduction apparatus, while U.S. Pat.No. 6,125,852 describes minimally-invasive devices and methods fortreatment of congestive heart failure, at least some of which involvereshaping an outer wall of the patient's heart so as to reduce thetransverse dimension of the left ventricle. U.S. Pat. No. 6,616,684describes endovascular splinting devices and methods, while U.S. Pat.No. 6,808,488 describes external stress reduction devices and methodsthat may create a heart wall shape change. Each of these patents is alsoincorporated herein by reference.

While these and other proposed implants may help surgically remedy thesize of the ventricle as a treatment of congestive heart failure andappear to offer benefits for many patients, still further advances wouldbe desirable. In general, it would be desirable to provide improveddevices, systems, and methods for treatment of congestive heart failureand other disease conditions of the heart. It would be particularlydesirable if such devices and techniques could increase the overalltherapeutic benefit for patients in which they are implanted, and/orcould increase the number of patients who might benefit from theserecently proposed therapies. Ideally, at least some embodiments wouldinclude structures and or methods for prophylactic use, potentiallyaltogether avoiding some or all of the deleterious symptoms ofcongestive heart failure after a patient has a heart attack, but beforeforeseeable disease progression. It would be advantageous if theseimprovements could be provided without overly complicating the deviceimplantation procedure or increasing the trauma to the patientundergoing the surgery, ideally while significantly enhancing thebenefits provided by the implanted device.

BRIEF SUMMARY OF THE INVENTION

The present invention generally provides improved devices, systems, andmethods for treating a heart of a patient. Embodiments of the inventionmay make use of structures which limit a size of a chamber of the heart,such as by deploying one or more tensile member to bring a wall of theheart and a septum of the heart toward each other (and often intocontact). A plurality of tension members may help exclude scar tissueand provide a more effective remaining ventricle chamber. Embodiments ofthe implant may be deployed at least in part during beating of theheart, often in a minimally invasive or less-invasive manner thantraditional open chest, open heart, and/or bypass-based therapies.Trauma to the tissues of the heart may be inhibited by selectivelyapproximating tissues while a pressure within the heart is temporarilyreduced, optionally by applying a limited tension force, by selectivelyreducing a length of the tension member during diastolic pressurereductions, by selectively blocking blood flow into the heart, by pacinga ventricle of the heart at a rate sufficiently fast to inhibit pressurebuildup, and/or the like. Three-dimensional implant locating devices andsystems facilitate beneficial heart chamber volumetric shape remodeling,and refined deployment/measurement bodies (optionally having axialcurvatures substantially corresponding to an adjacent chamber diameter)increase the accuracy and ease with which such remodeling may beeffected. A variety of additional devices and methods for their use arealso provided, including a pattern for positioning anchors of implants.

In a first aspect, the invention provides a method for treating a heart.The method comprises decreasing, during beating of the heart, a distancebetween a first location (that borders a chamber of the heart) and asecond location (also bordering the chamber of the heart). The distanceis selectively decreased while a pressure within the chamber istemporarily reduced so as to permanently and safely reduce a volume ofthe chamber.

Prior to initiation of the treatment, beating of the heart willtypically induce a relatively high systolic pressure and a relativereduced diastolic pressure. The distance between the first location andthe second location will often be selectively and permanently decreasedwhile the pressure within the chamber is less than the pre-treatmentsystolic pressure. Anchors are typically deployed at the first andsecond locations, with the locations of the heart tissue beingapproximated by applying tension between the anchors when pressure inthe chamber is less than the systolic pressure. The tension can beapplied, for example, by incrementally decreasing a length of a tensionmember extending between the anchors between systolic pressure peaksusing a tension force that is sufficient to overcome the diastolicpressure but which does not result in approximation during the systolicpressure. By avoiding shortening of the tension member (and movement ofthe anchors away from each other) during the systolic pressure peaks,the stresses imposed on the beating heart may be maintained within safelimits. In other embodiments, blood flow into the chamber may beinhibited so as to temporarily decrease pressure within the chamber,allowing the tension to be selectively applied while again limitingstress to the heart tissues. Expansion of a balloon of a ballooncatheter may be used to inhibit the blood flow into the heart. Stillfurther heart pressure limiting techniques may be used, including pacingof the ventricle at a relatively rapid rate, with the rate beingsufficiently fast to limit total pressure and stress on the tissues.Suitable ventricle pacing rates may be in a range from about 180 toabout 240 beats per minute, typically being between about 200 and 210beats per minute with adjustments beyond this narrower range forpatients with significantly weakened hearts, for limiting blood pressureto a desired range, and/or the like.

In many embodiments, a plurality of laterally off-set implants will beused. The separation distances between anchor pairs of each implant maybe decreased so as to effectively exclude scar tissue of the heart fromthe chamber, thereby mitigating congestive heart failure (CHF) of theheart. Some or all of the anchors may be deployed so as to penetratescar tissue, rather than viable contractile tissue of the heart. Notethat some scar tissue may remain exposed within the treated chamber. Atleast some of the separation distances may be reduced simultaneously,and/or at least some of the separation distances may be reducedsequentially. The treatment may be performed in an open procedure (oftenby accessing at least the outer pericardium of the heart and optionallywithout imposing the trauma of opening the heart chamber itself), in aless invasive manner (such as through a subxiphoid incision or the like)or in a minimally invasive manner (such as through the use of catheterbased deployment systems and remote imaging, robotically assistedsurgery, or the like).

In another aspect, the invention provides a method for treating adiseased heart. The method comprises reducing, in a first cross section,a first size of a chamber of a heart. The size is reduced byapproximation of a first anchor location toward a second anchorlocation. The anchor locations are disposed near edges of a diseasedtissue bordering the chamber. For a second cross section, a secondreduction in size of the chamber is determined in response to an axialoffset between the first cross section and the second cross section, andin response to a magnitude of the first reduction in cross section ofthe chamber. The determined second reduction in size of the chamber iseffected by deploying third and fourth anchors into tissues of the heartbordering the chamber, and by reducing a length of a tension memberextending between the third and fourth anchors.

Optionally, the magnitude of the first or second reduction in crosssection may be identified using a body which extends between thelocations of an anchor pair. The chamber will typically have a diameterassociated with each cross section, and the diameter may define acurvature. The body may have an axial curvature that substantiallycorresponds to the chamber curvature adjacent the anchor pair, so thatapproximation of the anchors results in a circumferential reduction insize of the chamber that corresponds to the length of the body extendingbetween the anchor locations. This allows calculation of the effectivechange in diameter that will be generated by various anchor locations,and may facilitate computation of appropriate volumetric changes alongan axial length of the heart chamber to produce a beneficial overallremodeling that enhances pumping effectiveness of the heart. Note thatnot all of the anchor locations may be dictated by the extent of scartissue in a particular cross section, though at least some may be. Toresult in a desired longitudinal cross section of the heart, individualaxial cross sections may each be determined at least in part in responseto a diseased size of the cross section before treatment, an offsetbetween the first cross section and the cross section to be treated, anda magnitude of the first cross section.

In another aspect, the invention provides a method for treating adiseased heart comprising aligning an anchor pattern template with achamber of the heart. The anchor pattern template identifies a pluralityof anchor locations, and anchors are deployed into the heart tissue perthe aligned template. Tension is applied between associated anchors soas to approximate tissue adjacent the associated anchors and reduce aneffective size of the chamber.

The anchor pattern template may be inserted into the chamber in a smallprofile configuration, and may be expanded in situ to a large-profileconfiguration within the chamber, such as by unrolling a flexible anchorpattern template membrane material from about a catheter or the like.Alternative embodiments might be deployed around an outer surface of theheart or chamber. The anchor pattern template will often be aligned withthe scar tissue of the heart so that the desired volumetric remodelingeffectively excludes the scar tissue from the chamber.

In another aspect, the invention provides a system for treating a heart.The system comprises first and second anchors for coupling to first andsecond locations bordering a chamber of the heart. A tension membercouples the first anchor with the second anchor. The tension member isconfigured to be selectively shortened from an elongate configuration toa shortened configuration in situ. A pressure component is configuredfor fluid communication with the chamber and indicates or effects areduction in blood pressure for selectively shortening the tensionmember to reduce size of the chamber. The selective shortening can occurwhile the heart is beating and the pressure component facilitatesselective shortening while pressure within the chamber is temporarilyreduced.

In another aspect, the invention provides a system for treating adiseased heart. The system is for use with first and second implants,each implant including a pair of anchors coupleable to associated anchorlocations bordering a chamber of the heart. Each implant also includes atension member for coupling the anchors together so as to reduce, in anassociated cross section, a size of the chamber of the heart. The systemcomprises a processor configured for determining, for at least one ofthe cross sections, an associated reduction in size of the chamber. Thereduction in size of the chamber is determined in response to inputsthat include an offset between the first cross section and the secondcross section, and a magnitude of another reduction in cross section ofthe chamber. The processor will often output a display of the determinedreduction in size of the chamber. Typically, the processor will beconfigured to determine the reduction in cross section using electronicdata processing circuitry running machine readable programming thatembodies instructions for calculating the desired reduction in chambersize.

In yet another aspect, the invention provides a system for diagnosing ortreating a diseased heart. A chamber of the heart has a diameterdefining a curvature between a first location and a second location. Thesystem comprises a body extendable from the first location to the secondlocation. The body has an axis with an axis curvature substantiallycorresponding to the curvature of the chamber, so that a curving lengthof the body between the locations approximates a circumference of thewall between the locations.

In exemplary embodiments, the system will include a plurality of anchorpairs and associated tension members for approximating heart tissues. Aprocessor will also be included, with the processor being configured fordetermining, for a plurality of cross sections of the heart, anassociated treatment of the chamber. Each treatment will comprise areduction in size of the cross section, and may be determined inresponse to a diseased size of the chamber in the cross section beforethe treatment, an offset between the cross sections, and/or a magnitudeof at least one of the reductions in cross sectional size of the heartchamber. This cross section-by-cross section calculation of the changein size of the heart chamber may be used to provide the chamber with adesired volumetric shape, with the cross sections often being takentransverse to an axis of a ventricular chamber running from the mitralvalve to the lower chamber apex. Use of a curving body (the curvesubstantially corresponds to that of the chamber wall) allows changes inthe circumference of the chamber to be effected with enhanced accuracy.

In another aspect, the invention provides a device for treating adiseased heart. The device is used with a plurality of anchors and/orimplants. The device comprises an anchor pattern template for aligningwith a chamber of the heart. The anchor pattern template comprisesindicia identifying a plurality of anchor locations such that when theanchor pattern template is aligned with the chamber, the plurality ofanchors are deployed into tissue of the heart per the indicia, andtension is applied between the deployed anchors so as to approximate thetissue, and effective size of the chamber is reduced.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view schematically illustrating a knownimplant and method for closing off a lower portion of a heart ventricle,as described in the background section.

FIG. 2 schematically illustrates a side view of the lower portion of theheart, showing how three implants together reduce the effective size ofthe left ventricle by effectively excluding a region of scar tissue fromthe septum and left ventricle wall.

FIGS. 2A and 2B schematically illustrate deployment of three laterallyoffset implants to effectively exclude a portion of the left ventricle.

FIGS. 2C and 2D schematically illustrate a single implant having threelaterally offset tension members for effectively excluding a region ofscar tissue from the left ventricle.

FIGS. 3A and 3B illustrate examples of images of the heart and/ordevices disposed therein that may be used to direct deployment ofembodiments of the invention.

FIGS. 4A-4E are cross-sectional views schematically illustrating methodsfor accessing, identifying, and penetrating tissues for deployment ofthe implant system of FIGS. 2 and 2A.

FIGS. 5A and 5B are cross-sectional views schematically illustratinginitial deployment of an implant of the system of FIGS. 2A and 2B, withthe implant initially being deployed in an elongate configuration.

FIGS. 6A-6D illustrate deployment of an anchor for use in the implant ofFIG. 5B.

FIGS. 7A and 7B are cross-sectional views schematically illustratingshortening of the tensile member of FIG. 5B from the elongate initialconfiguration to a shortened deployed configuration so as to reduce asize of the left ventricle and effectively exclude at least a portion ofa scar tissue from the left ventricle.

FIG. 8 schematically illustrates an alternative anchor structure in theform of a inflated balloon, an annular balloon disposed within a wall ofthe left ventricle so as to inhibit blood flow through a perforation,and treating a myocardial tissue surface with mechanical energy from abur or the like to promote adhesion formation.

FIG. 9 schematically illustrates accessing the heart via a subxiphoidincision.

FIG. 10 illustrates a method for unloading of the heart with a doubleballoon catheter.

FIGS. 11A-11C schematically illustrate one variation of atransventricular implant and anchor system from a left ventricularapproach.

FIGS. 12A and 12B schematically illustrate another variation of atransventricular implant and anchor system from a right ventricularapproach.

FIG. 13 illustrates a double balloon catheter for unloading of the heartin the method of FIG. 10.

FIGS. 14A-14C schematically illustrate another variation of atransventricular implant and anchor system from a left ventricularapproach.

FIGS. 15A-15E are cross sections schematically illustrating deploymentof an alternative implant structure so as to approximate the tissues ofa heart, with the implant here employing anchors that rotate to alarge-profiled deployed configuration relative to the tension member.

FIG. 16 illustrates an outer surface of a heart in which a pattern ofimplants has been deployed to effectively exclude scar tissue andprovide a desired volumetric reshaping of the chamber of the heart.

FIGS. 17A and 17B are partial cross sectional views schematicallyillustrating a partially and fully expanded anchor pattern template foridentifying locations of anchors so as to achieve a desired volumetricremodeling of a chamber of the heart.

FIGS. 18A-18C schematically illustrate calculations of a desiredresizing for one cross section of the heart, and the use of a curvedmeasurement and/or tensile member shortening body for providing a knowncircumferential reduction (and hence change in diameter) of the heartchamber cross section.

FIGS. 19A and 19B schematically illustrate the processor system andmethod for determining an appropriate pattern of implant anchorlocations so as to volumetrically reshape the chamber of the heart.

DETAILED DESCRIPTION OF THE INVENTION

The present invention generally provides improved devices, systems, andmethods for treatment of a heart. Embodiments of the invention may beparticularly beneficial for treatment of congestive heart failure andother disease conditions of the heart. The invention may find uses as aprophylactic treatment, and/or may be included as at least a portion ofa therapeutic intervention.

Myocardial infarction and the resultant scar formation is often theindex event in the genesis of congestive heart failure. The presence ofthe scar may, if left untreated, lead to a compensatory neuro-hormonalresponse by the remaining, non-infarcted myocardium. The systems,methods, and devices described herein may be applied to inhibit,reverse, or avoid this response altogether, often halting a destructivesequence of events which could otherwise cause the eventual failure ofthe remaining functional heart muscle.

Embodiments of the present invention may build on known techniques forexclusion of the scar and volume reduction of the ventricle. Unlikeknown techniques that are often accomplished through open surgery,including left ventricular reconstruction, ventricular restoration, theDor procedure, and the like, the treatments described herein will often(though not necessarily always) be implemented in a minimally invasivemanner. Embodiments of the invention can provide advantages similar tothose (for example) of surgical reconstruction of the ventricle,resulting in improved function due to improved dynamics, and bynormalizing the downward cycle initiated by the original injury andmediated by the neuro-hormonal disease progression response.

Advantageously, the methods, devices, and systems described herein mayallow percutaneous left ventricular scar exclusion and ventricle volumereduction to be applied at any appropriate time during the course of thedisease. Rather than merely awaiting foreseeable disease progression andattempting to alleviate existing cardiac dysfunction, the techniquesdescribed herein may be applied proactively to prevent some or all ofthe heart failure symptoms, as well as to reverse at least a portion ofany existing congestive heart failure effects, to limit or halt theprogression of congestive heart failure, and/or to retard or preventcongestive heart failure disease progression in the future. Someembodiments may, for appropriate patients, limit the impact ofmyocardial infarction scar formation before heart failure everydevelops.

Referring now to the schematic illustration of FIG. 2, a side view of alower portion of the heart H schematically illustrates how a size of thechamber of the heart can be limited using a plurality of implants.Implants 12 extend through the left ventricle (through the plane ofillustration) so that only anchors of the implants are visible on theepicardial surface of the heart. By using a plurality of laterallyoffset anchors 12, a left ventricle LV is reduced from an initial sizeto a smaller effective size by engagement between the inner surfaces ofthe septum and left ventricle wall. A region of engagement 14 betweenthese endocardial surfaces extends between the implants 12 andeffectively excludes scar tissue along the lower portion of the septumand/or left ventricular wall from the functioning left ventricle. Byarranging the implants 12 across some or all of the left ventricle, theremaining contractile tissue of the ventricle can make effective use ofthe reduced chamber volume to provide more effective pumping of theblood from within the heart, and may also avoid excessive stagnant voidsthat remain in fluid communication with the blood flow that mightotherwise collect and release thrombus.

Referring now to FIGS. 2A and 2B, a schematic top view shows threelaterally offset implants 42 that can be used to, in combination,effectively exclude scar tissue from left ventricle LV. In theillustration of FIG. 2A, each implant is shown in an elongateconfiguration. More specifically, each implant 42 extends distally froman associated deployment catheter 46 to a distal left ventricular wallanchor 50. A septal anchor 48 is coupled to the wall anchor 50 by atension member 52. The tension member 52 of the implants 42 are offsetlaterally, with the tension members here shown extending roughlyparallel to each other across the left ventricle LV. In otherembodiments, the tension members may be disposed at an angle relative toeach other, and may even extend across each other. Nonetheless, bypositioning the anchors laterally offset of each other, effectiveexclusion of scar tissue from the left ventricle LV may be enhanced.

Referring now to FIG. 2B, implants 42 are shown fully deployed, withdeployment catheters 46 detached from the implants and removed from theheart, and tension members 52 axially shortened from the elongateconfiguration of FIG. 2A to a shortened, tensioned configuration.Implants 42 in the shortened configuration draw endocardial surfaces ofthe wall W into engagement with the corresponding endocardial surfacesof septum S sufficiently to effectively exclude at least a portion ofthe scar tissue from the functioning lower ventricle. Note that theengagement need not be absolute along the entire cross section of thelower ventricle, so long as scar tissue is effectively excludedimmediately after the procedure or, after an initial tissue response tothe implant(s), at least some of the scar tissue is not subjected to thestress of being included in the pumping left ventricle. This may improvepumping efficiency of the remaining left ventricle and may limit diseaseprogression from enlarged heart wall tissue stresses.

Referring now to FIGS. 2C and 2D, alternative implants 42′ may alsoinclude a septal anchor 48 and a wall anchor 50, with a tension member52 extending therebetween. Such alternative implants may, in some cases,have multiple wall anchors 50 associated with each septal anchor 48, ormultiple septal anchors associated with each wall anchor. The tensionmembers 52 may extend in positions that are both angularly and laterallyoffset from each other. As shown in FIG. 2D, axial shortening of thetension members between the anchors 48, 50 may leave a portion of thetension member extending into the extra-cardiac space. In someembodiments, one or a plurality of implants may provide a bunchingengagement of endocardial tissues, with the engagement extending uponmultiple fold lines so as to effectively exclude at least a portion ofthe scar tissue. Some or all of the components of the implants may bepositioned using an epicardial access approach, with or withoutendocardial delivery or deployment catheters 46 (see FIG. 2A) for otherimplant components.

Referring now to FIGS. 3A and 3B, deployment of the implants describedherein and implementation of the therapies will benefit from accurateand reliable identification of the margins separating the scar andviable, contractile myocardium. Such identification can be accomplished,for example, using pre-operative imaging, catheter-sensed activationpotentials, pacing thresholds, ultrasonic imaging characteristics,biomarkers, or a variety of other tissue imaging and/or characterizationmethodologies. Additional exemplary tissue characterization (and/ordifferentiation between scar and viable contractile tissues) may employMRI tissue characterization techniques with or without the use ofcontrast agents. In general, it will be beneficial to provideinformation to the physician deploying the system to allow accuratecharacterization of selected locations as substantially comprising scartissue or substantially comprising a viable contractile tissue.Additionally, the geometry of the chambers of the heart, andparticularly the left ventricular chamber, should be clearly imaged tofacilitate the desired reduction in size of the left ventricularchamber. This imaging may be accomplished by one imaging modality or bya combination of different imaging modalities. Exemplary imagingmodalities which may be employed for identification of the heartgeometry and/or tissue characterization include: echocardiography(including intracardiac echocardiography (“ICE”) and/or extra-cardiacechocardiography (such as transesophageal echocardiography and/ortransthoracic echocardiography (“TTE” and “TEE”, respectively) or thelike), intra- or extra-vascular endoscopy, fluoroscopy, or any of avariety of alternative existing or new imaging techniques, either aloneor in combination.

FIGS. 3A and 3B illustrate an example of ICE showing the geometry of theheart chambers, including a right atrium RA, a portion of the rightventricle RV, and the left ventricle LV along with some of the hearttissues bordering these chambers. FIG. 3B illustrates an intracardiacechocardiography image in which a catheter device within the ventriclecan be seen.

Deployment of the structures described herein may also benefit fromsensors that can be used to monitor the procedure, such sensors ideallyproviding a real-time assessment of the progress of the treatment andperformance of the heart during deployment and/or as deployment iscompleted. The goal of deployment will often be to achieve a desiredreduction in size of a chamber (typically the left ventricle), whileavoiding overcorrection (which might otherwise induce acute diastolicdysfunction). Such functional assessment sensors may comprise pressuresensors, hemodynamic sensing systems, strain sensors, oxygen saturationsensors, biological marker detectors, and/or other sensors measuringheart function to permit a quantitative assessment of efficacy of theprocedure as it is implemented.

Referring now to FIGS. 4A-4E, exemplary techniques and structures foraccessing and penetrating the septum and left ventricular wall can beunderstood. First summarizing these steps, it will be advantageous toidentify, engage, and temporarily hold the device in alignment with adesired position on the right ventricular septum, as schematicallyillustrated in FIG. 4A. Identification or characterization of theengaged tissue will also be advantageous. The septum will be penetratedas can be understood with reference to FIG. 4B, and the system issteered across the left ventricular chamber as illustrated in FIG. 4C.The system engages one or more target locations on the left ventricularwall as shown in FIG. 4D. The engaged tissue may be characterized andthe system repositioned as needed, with the system being held inengagement with the left ventricular wall if found to be at anappropriate or designated position, with the system optionally attachingor temporarily affixing itself to the left ventricular wall. The leftventricular wall may then be perforated, penetrated, or otherwisetranscended as illustrated in FIG. 4E. As indicated above regardingFIGS. 3A and 3B, target tissue access, penetration, and implantdeployment may be performed with reference to ICE within the bloodstream of the vascular system, with the ICE images typically comprising2-D sector images, the sectors often comprising an about 60 degreesector.

In more detail, referring now to FIG. 4A, an access and deploymentsystem 70 includes a catheter 72 and a penetrating/sensing perforationdevice 74. In some embodiments, separate probes may be used forpenetrating the heart tissues and characterizing the tissues. Here,catheter 72 accesses the right ventricle RV in a conventional manner,typically by advancing the catheter over a coronary access guidewire. Adistal end of catheter 72 is aligned with a candidate location along theright ventricular surface of the septum S by a combination of axialrotation of the catheter and distal/proximal positioning of thecatheter, as shown by the arrows. Positioning of the catheter isdirected with reference to imaging (as described above) and when the endof the catheter is aligned with the candidate location a perforationdevice 74 is advanced distally so that a distal end of the perforationdevice contacts the septum S.

Perforation device 74 may characterize or verify that the candidatelocation is appropriate, for example, by determining a pacing thresholdat the candidate site. Scar tissue ST may have a pacing threshold whichdiffers sufficiently from a viable tissue VT to allow the physician toverify that the candidate site comprises scar tissue and/or is otherwisesuitable. If the candidate site is not suitable, the perforation device74 may be withdrawn proximally to disengage the perforation device fromthe septum S, and the catheter may be repositioned as described above toa new candidate site.

Catheter 72 may comprise a commercially available steerable sheath orintroducer. Deflection of catheter 72 may be effected using one or morepull wires extending axially within the catheter body. Suitableintroducers include devices that can be introduced transcutaneously intoa vein or artery. Suitable steerable sheaths may generally comprise atubular catheter body with an open working lumen. The open lumen can beused as a conduit for passing another catheter into the patient body, orfor introducing another device (such as a pacing lead) into the patientbody. Exemplary steerable sheaths for use in system 70 may include thosecommercially available from the Diag division of the St. JudeCorporation, from Medtronic, from Bard, and/or from others. Preferably,the working lumen of catheter 72 will be in a range from about 5 F-11 F.Alternative systems may employ a flexible sheath removably receiving asteerable catheter or other device therein, the steerable catheteroptionally comprising a steerable electrophysiology catheter or a devicederived therefrom. Still further embodiments may employ pre-bent cardiacaccess catheters.

Regarding perforating device 74, one embodiment would comprise adeflectable or steerable catheter body (ideally comprising a 2 F-3 Fcatheter) with a metallic rounded and/or bullet-shaped electrode at itsdistal end. The distal electrode is connected to a signal wire thatterminates in a connector outside the body. Electrogram amplitudesrecorded from the distal electrode can be used to help determine if thedistal tip is located over scar tissue or over viable tissue. Efficacyin characterization of engaged heart tissues (between scar tissue andviable heart tissue) may be enhanced by recording the differentialsignal between the tip electrode and a band electrode located less than1 cm from the distal electrode.

Pacing from the distal tip can be employed to help avoid perforationthrough viable myocardium. For most patients, such a perforation sitewould be counter-indicated. If the heart can be paced from the tip usinga 10V amplitude pacing pulse, then viable myocardium will generally bedisposed within about 5 mm of the tip. When the proper penetration sitehas been identified, then the distal tip is electrically coupled to anelectrosurgical power source unit, and penetration is enabled byapplying power to the tip in cut mode. At proper power settings, thisperforation method can allow a clean perforation channel to be createdwithout the tearing that can otherwise occur with physical perforationof the septum or free wall.

Once an appropriate site has been identified and verified, the system isheld in alignment with the candidate site, and may optionally be affixedtemporarily at the verified site. Perforation device 74 is advanceddistally into and through septum S as illustrated in FIGS. 4B and 4C.Perforation device 74 may have a sharpened distal tip, a rotatablehelical or screw structure, or other mechanical attributes to facilitatepenetration into and perforation through the myocardium. Energy deliveryelements (such as electrosurgical energy, laser energy, or the like) mayalso be provided. In some embodiments, system 70 may employ componentssimilar to or modified from known septum traversing systems used foraccessing the left ventricle. In general, it may be advantageous to seekto perforate tissue with an axis of perforation device 74 orientedacross the ventricle and straight toward or near a suitable target sitefor the subsequent perforation, as imposing excessively acute angles onthe heart tissue may weaken or even tear the heart tissue.

As can be understood with reference to FIGS. 4C and 4D, once perforationdevice 74 has penetrated through the septum S, manipulation of thecatheter 72 under the guidance of the imaging system allows theperforation device to be steered across the left ventricle LV and intoengagement with a target location along the wall of the left ventricle.The tissue at this target location may be characterized using a sensorof perforation device 74, pacing of the engaged tissue, or the like, andthe end of the perforation device repositioned as needed. The preferredlocation for deployment of the implant may be along or adjacent to scartissue ST. In some embodiments, system 70 may be used for positioning ofa lead at a location separated from the axis of the implant tensioningmember. System 70 also allows for epicardial lead placement by advancingthe perforation device 74 endocardially through septum S and themyocardium of the left ventricular wall W until it is located on theepicardial surface of the heart. The perforation device 74 and/or leadmay be at least temporarily fixed at that location and tested for properpacing effect, as can be understood with reference to FIGS. 4E and 5B.

The access and deployment system 70 described above with reference toFIGS. 4A-4E may be supplemented with or replaced by a number ofdiffering system components. For example, as can be understood withreference to FIG. 5A, a balloon catheter 80 or other sealing structuremay be used, optionally being advanced within catheter 72 and/or overperforation device 74. The balloon of balloon catheter 80 may bepositioned within the myocardium of septum S or the left ventricularfree-wall W to anchor the deployment system temporarily to the hearttissue and control blood loss, particularly blood loss through the leftventricular wall into the extra-cardiac space. In some embodiments, twoseparate balloons may be used to seal both the septum and the leftventricular wall. Balloons may also be used with or as anchors of theimplant device.

Still further alternative structures may be employed, perforation device74 may have any of a variety of sensors, including pressure sensors andthe like. System 70 will often comprise high contrast structures toenhance imaging, such as by including materials having highradio-opacity, echo-density, or the like. As noted above, perforationdevice 74 may have or be used with a cutting, drilling, or othermechanism to help in tissue penetration. Still further alternativestructures may be used for steering and positioning of the deploymentsystem and perforation device. For example, rather than manuallymanipulating or steering catheter 72 to position and orient the implant,the deployment system may employ robotic surgical techniques such asthose now being developed and/or commercialized for manipulation ofcatheters. Magnetic steering of the catheter end may also be employed,and any of a wide variety of mechanical steerable or pre-formed catheterstructures could be employed. Some or all of the components may accessthe left and/or right ventricular chambers using an epicardial approach,rather than the endovascular approach described above. A combination ofan extra-cardiac and intracardiac approach may also be employed, withthe components of the implant being introduced in any of a wide varietyof techniques. In some embodiments, implant 42 and/or other componentsof the system may be deployed in an open surgical procedure. Directlyaccessing at least the epicardial surface of the heart may significantlyfacilitate positioning and deployment of implant 42, particularly fordevelopment of implant system components and techniques, including thosewhich may later be deployed in a minimally invasive manner.

Referring now to FIGS. 5B and 6A-6C, implant 42 is deployed throughcatheter 72 of deployment system 70, with the implant initially beingdeployed in an elongate configuration extending across left ventricleLV. Anchors 48, 50 of implant 42 advance distally through a lumen ofcatheter 72 while the anchor is in a small profile configuration, asillustrated in FIG. 6A. Anchor 50 expands from the small profileconfiguration to a large profile configuration, which may be effected byaltering a distance between a distal end 82 and a shaft of tensionmember 52 using elongate bodies 84, 86 detachably coupled to the distalend 82 and tension member 52, respectively.

In general, anchors 48, 50 will be deployable through, over, or adjacentto the myocardium tissue penetrating components of deployment system 70.The anchors will attach to or otherwise engage the wall, usually byexpanding or inflating into a cross section larger than that of thepenetration through the heart tissue. A wide variety of anchorstructures may be employed, including structures that form a disk-shapedsurface or lateral extensions from an axis 90 of implant 42. As can beunderstood with reference to FIG. 60, an inflatable bladder 92 orballoon of appropriate shape may be used alone or in combination withother anchoring structures. If an inflatable bladder or balloon is used,it may be filled with a substance which is initially introduced as aliquid, but which reversibly or irreversibly solidifies. Suitable fillmaterials may, for example, comprise liquid silicone rubber, which canpolymerize at any of a variety of alternative desired rates depending onthe chemistry of the material used. Optionally, the material maysolidify over more than one hour, optionally over many hours or evendays at body temperatures. During a procedure, such an injected liquidcould be removed if desired, but the material would eventually solidify.Biological adhesives could also be delivered as fluid to fill a balloon,though cure times are relatively shorter for such materials. Suchmaterials would irreversibly solidify.

The septal and left ventricular wall anchors 48, 50 may be identical orsimilar in structure, or may differ to reflect the differences betweenthe epicardial and endocardial surfaces they engage. Fixation to thewall and septum will generally be sufficient to support the tension oftensile member 52, which will generally be capable of approximating thewall and septum, typically maintaining proximity or engagement betweenthese structures during beating of the heart. Anchors 48, 50 and tensilemember 52 will often comprise high-contrast materials to facilitateimaging, such as by including materials of sufficient radio-opacity,echo density, and the like.

In some embodiments, implant 42 may be used alone or with similarimplants to effect volume reduction over a length, width, or volume ofthe ventricular wall. When at least a portion of the implant 42 isdeployed using an epicardial approach, left ventricular anchor 50 willoften be included in the components attached from outside the heart,with tensile member 52 and/or anchor 48 being attached to thisepicardial component during deployment. Robotic structures may be usedto position the intracardiac or extra-cardiac components, and/or toattach the two of them together.

Referring again to FIGS. 6A-6D, the exemplary anchor structure comprisesa Nitinol™ shaped memory alloy or other flexible material formed into atubular shaft. Axial cuts 94 may be formed along this tubular shaft,with the cuts having a desired length and being disposed near distal end82. Anchor 50 is advanced until the most proximal margin of cuts 94extends clear of the heart tissue. A retraction member 96 (optionallybeing releasable attached to the associated elongate body 86) fixed tothe inside of distal end 82 is retracted proximally, expanding the wallsof the tubular shaft radially into the circumferential series of arms98. Tissue engaging surfaces 100 of arms 98 may be substantiallyperpendicular to axis 90 of the implant. Arms 98 may have two generalcomponents, including the portion of the arm along tissue engagingsurface 100 and a slightly longer bracing portion of the arm 102extending away from the tissue engaging surface along axis 90. Theproportionate sizes of these two elements of arms 98 may bepre-determined by localized altering of the arm stiffness (effecting theplacement of living hinges) or the tubing material will otherwisepreferably bend so that the arms assume a desired shape. The deployedarms may have, for example, the pyramid shape shown with the tissueengaging surface 100 supported by angled portions 102 with apyramid-like force distribution, the angled bracing portions forming atriangular relationship with the surface of the heart wall.

Member 96 may remain within the deployed anchor, axially affixingtensile member 52 relative to the end of the anchor after deployment ofthe implant. This can help inhibit collapse of the arms 98. In someembodiments, arms 98 may be biased to the large cross section deployedconfiguration, such as by appropriate treatments to a shape memory alloyor the like. In such embodiments, member 98 or some other actuationstructure may restrain the anchor in a small cross sectionconfiguration, it may not remain within the deployed implant after it isexpanded.

As can be understood with reference to FIG. 60, once the anchor 50 isdeployed and in position, additional support elements may be positionedor deployed through the deployment system 70. For example, a spaceoccupying or expandable structure such as bladder 92 may be positionedor inflated within arms 98, internal support structures (optionallycomprising internal pyramid-like support arms) may be deployed. Theseptal anchor 48 will optionally have a structure similar to anchor 50,with the proximal and distal orientations of the arm structuresreversed.

While anchor 50 of FIGS. 6A-6D is shown as being integrated into atubular shaft of elongate tensile member 52, the anchor or fixationdevice may alternatively comprise a separate element introducedseparately over a guidewire or the like. Still further alternatives maybe employed, including fixation of the heart walls by placement ofmagnetic materials on or within the walls, with the bodies acting asanchors and the magnetic material acting as a tensile component so as tohold the walls in apposition.

Anchors 48 and/or 50 may optionally be drug eluting. For example,bladder or balloon 92 may have a porous surface capable of eluting asubstance from the film material. Alternatively, an outer surface of theballoon or the anchor structure itself may comprise a permanent orbiodegradable polymer or the like, such as those that have beendeveloped for drug eluting stents and available from a number ofcommercial suppliers. Drugs eluted from the implants may include any ofthe compositions eluted from drug-eluting stents.

Referring now to FIGS. 5B, 7A, and 7B, after anchors 48-50 are deployed,implant 42 may be shortened from its elongate configuration with arelatively large distance between the anchors along tensile member 52 toa shortened configuration. In some embodiments, the tensile member maycomprise a shaft of the tissue penetrating perforation device 74 (seeFIGS. 4A-4E). In other embodiments, tensile member 52 will comprise aseparate structure. In many embodiments, the tensile member and anchorswill remain permanently in the heart to hold the septum and leftventricular wall in apposition. To allow shortening of the tensilemember, excess length of the tensile member may be removed with thecatheter 72 and other components of the delivery system, and/or someportion of the length of the tensile member may remain in theextra-cardiac space outside the left ventricular wall.

Optionally, a ratchet mechanism may couple the septal anchor 48 to thetensile member 52, with the ratchet mechanism allowing the separationdistance between the anchors to gradually decrease. While exemplaryratchet mechanisms are described below with reference to FIGS. 11A-11C,12A and B, and 14A-14C, a wide variety of alternative structures thatcan be reconfigured in situ to alter the separation distance between theanchors might alternatively be employed.

Referring now to FIG. 8, additional optional elements for the implantsand/or deployment systems described herein can be understood. Here, aguidewire 102 is shown extending through a perforation of leftventricular wall W, with components of the deployment system and/orimplant advanced over the guidewire. A deployment catheter sheath 104may be used with or without guidewire 102. Guidewire 102 and/or sheath104 may be steerable to facilitate access and deployment of the implant.

A temporary or permanent anchor is here provided by a balloon 106. Anaxially-oriented portion of the outer surface of balloon 106 engages theadjacent epicardial surface of wall W to pull the wall towardsengagement with the septum, as described above. Balloon anchor 106 maycomprise a structure similar to a balloon of a balloon catheter, with anexpandable and biocompatible bladder material defining the balloon wall.Along with the exemplary fill materials described above, the fillmaterial may generally comprise a reversibly or irreversibly hardenablepolymer, and the bladder material may have pores to allow eluting ofdrugs from the fill material or fluid.

An annular expandable structure such as annular balloon 108 on anassociated catheter 110 may expand within the myocardium from theperforation or penetration through the left ventricular wall W or septumS. Balloon 108 may help to temporarily hold the deployment system inposition relative to the perforation and tissue structures, or may insome embodiments be used as a permanent anchor (with or withoutadditional anchoring structures). Temporary deployment of balloon 108against the myocardial tissues may be particularly advantageous duringor after perforation of the free left ventricular wall W duringdeployment of the wall anchor, as it may help to limit the release ofblood into the extra-cardiac space. Balloon 108 may comprise arelatively standard balloon catheter material, such as nylon, PET, orthe like.

Yet another aspect schematically illustrated in FIG. 8 is a probe 112having a surface 114 that treats the endocardial surface of the leftventricle wall W or septum S so as to promote formation of adhesions.Surface 114 may comprise a bur or other mechanical energy applicationsurface for imposing mechanical trauma on the tissues within the heart.In alternative embodiments, surface 114 may comprise an electrodesurface for applying electrosurgical energy, light refracting surfacefor applying visible or invisible radiation, one or more agent deliveryports for transmitting caustic or sclerosing agents to the heart tissue,or the like. Such surfaces may apply a controlled, limited trauma to thetissue surface regions of the left ventricular wall and/or septum so asto induce the formation of scar tissues bridging these two tissuestructures and forming permanent adhesions therebetween.

When a probe 112 or surface of the implant or delivery catheter is usedto promote formations of adhesions, or when the implant providessufficient compressive force between the left ventricular wall andseptum so as to promote adhesions without separately imposing a traumaon the tissue surface, some or all of the implant may comprisebiodegradable material. After the adhesions are fully formed and thebiodegradable material of the implant degrades, the natural adhesionsmay alone maintain the reduced size of the left ventricle, exclude scartissue from the effective left ventricle, and limit the effects ofcongestive heart failure. Suitable biodegradable materials for use inthe structural components of the implants described herein may includematerials developed for and/or used in biodegradable stent structures.

While an myocardial engagement balloon 108, balloon anchor 106, andtrauma inducing probe 112, are shown schematically together in FIG. 8,and while some embodiments of the methods and systems described hereinmay make use of all three of these components, many embodiments mayemploy only any one or any two of these optional structures.Additionally, while much of the above-description relates tointravascular access and deployment of at least a portion of theimplant, other embodiments may be deployed during laparoscopic or evenopen heart surgery. Such embodiments may be particularly beneficial forverification and tailoring of the pattern of multiple implants to beused for scar tissue exclusion and left ventricular volume reduction,with subsequent embodiments making use of the verified and/or refinedpatterns through an at least partially intravascular approach.

Referring now to FIG. 9, embodiments of the invention may be deployedusing a subxiphoid incision SI to access the heart, and/or theventricles of the heart. In some embodiments, additional access may beobtained through one or more intercostals space for one or moreinstruments. As shown in FIG. 10, a double balloon catheter 120 mayoptionally be used to unload the heart tissue. Double balloon catheter120 can provide inflow occlusion to decompress the ventricles, therebyreducing the systolic pressure. This may aid in reducing the ventricularvolume and/or in the exclusion of dysfunctional cardiac tissue. Doubleballoon catheter 120 may optionally be placed using open chest surgery.Alternatively, double balloon catheter 120 may be positioned usingminimal invasive techniques, such as via a femoral or subclavian vesselsor veins, and optionally being positioned percutaneously.

In some embodiments, double balloon catheter 120 may be positioned sothat one balloon is in the superior vena cava and one balloon is in theinferior vena cava, thus blocking most or even essentially all bloodflow from the body back to the heart. It may be easier to insert theballoon catheter either into the jugular vein or the femoral vein thanit is to place using a cardiac insertion site. An alternative (and in atleast some cases faster) way of off-loading the left heart is to inflatea suitably large compliant balloon in the pulmonary artery just abovethe pulmonic valve (proximal to the branching into the left and rightpulmonary arteries). A partially inflated balloon will tend to floatinto the pulmonary artery from the right atrium, since blood flowcarries it into that position. Hence, this may provide another method ofdecreasing preload on the ventricle.

With reference to FIGS. 11A-11C, one variation of a transventricularimplant and anchor system deployment from a left ventricular LVapproach. A sharpened, curved tissue piercing tubular body 122 piercesthe left ventricular wall, the septum, and extends back out through theright ventricular wall. This allows a ratcheted tension member 124 to beintroduced through the tissues of the heart within a lumen of tubularbody 122, with a first anchor 126 being attached to the tension memberafter insertion through the tubular body and expanded as described aboveor affixed after the distal end of the tension member extends free ofthe heart tissue. Regardless, once the tension member extends intoand/or through both ventricles, the tubular body 122 can be withdrawnproximally and a second anchor 128 can be moved distally along thetension member to engage the myocardial surface of the heart, as seen inFIG. 11B. Second anchor 128 may optionally pass through the lumen oftubular body 122 and expand radially, or may be coupled to tensionmember 124 after the tubular body is withdrawn.

An exemplary ratcheting interface between tension member 124 and secondanchor 128 may make use of a series of radial protrusions and/or detentsdisposed along an axis of the tension member. For example, the tensionmember may have slide surfaces which taper radially outwardly distallyalong the tension member to allow the anchor interface to slidesequentially over the slide surfaces in a distal direction, and detentsurfaces which are oriented distally to engage corresponding proximallyoriented surfaces of the anchor interface so as to inhibit proximalmovement of the anchor relative to the tension member. Second anchor 128may have a ratchet interface structure including (or derived from) thesealing components of a Touhy-Borst valve structure. Such an interfacemay resiliently deflect to pass the slide surfaces of the tension memberand may grab or engage the detent surface when the tension member ispulled distally. Such a valve structure may also be increased indiameter to release the tension member if desired and/or tightenedtowards its smallest diameter to immovably (and optionally permanently)affix the anchor relative to the tension member. Exemplary embodimentsof ratcheting tension member 122 may comprise polymers or metals,optionally comprising a polyester such as Mylar®, a thermoplastic suchas Nylon™, a stainless steel, a shape memory allow such as Nitinol™, orthe like.

As shown in FIG. 11C, second anchor 128 can be positioned along tensionmember 122 so as to effectively exclude scar tissue from the leftventricle and/or reduce a volume of the left ventricle. Some portion oftension member 122 may be disposed within the right ventricle, rightventricle scar tissue may be excluded, and/or the volume of the rightventricle may also be reduced. The tension member may be severed using ablade or the like as shown schematically, though some of the tensionmember may extend into the extracardiac space. In alternativeembodiments using different surgical approaches (such as when using thecatheter-based systems described above), at least a portion of thetension member may extend into the right ventricle or the like.

Referring now to FIGS. 12A and 12B, another alternative embodiment of animplant 130 and deployment system makes use of a transventricularapproach from the right ventricle. A curved tension member 132 having adistal tissue penetrating end 134 and a proximal anchor 136 affixedthereto is introduced through the wall of the right ventricle, throughthe septum, across the left ventricle LV, and out through the leftventricular wall. The tension member 132 and affixed anchor 136 areadvanced distally so that the anchor engages the surface of the heart,and a second anchor 138 is attached by passing distal end 134 throughthe anchor. Second anchor 138 is ratcheted proximally along tensionmember 132 to exclude scar tissue and limit a size of the leftventricle, with the distal end and at least a portion of the tensionmember that is distal of the positioned anchor being severed and removedfrom the deployed implant.

FIG. 13 shows an exemplary double balloon catheter for use as describedabove with reference to FIGS. 9 and 10. Suitable structures totemporarily inhibit pressure within the heart may be introduced throughintravascular or extravascular access. In general, these structures canhave the effect, when deployed, of temporarily and reversiblydiminishing the left ventricular pressure and output. Suitable pressureinhibiting structures may include occlusive balloons that can beinflated in the right ventricular outflow tract (RVOT) to inhibit leftatrial filling. Other suitable occlusive structures may include clampsor the like which may be deployed on an outer surface of the RVOT.Regardless, such devices may be deployed in conjunction with theapproximation of the walls to minimize resistance caused by cardiacfilling and contraction against normal after load. FIGS. 14A-14Cschematically illustrate another transventricular anchor system anddeployment from a surgical site outside the heart similar to that ofFIGS. 11A-11C, using a tubular body 142 to position a tension member 142to which first and/or second anchors 146, 148 are ratchetably affixed.

It should be noted that the systems and methods described herein forexcluding scar tissue and reducing a size of a chamber of the heart maymake use of a plurality of different implants of different types andeven different surgical approaches. For example, while systems mayinclude a plurality of implants deployed from a site outside the heart(such as the embodiments shown in FIGS. 11A-11C, 12A and B, and14A-14C), alternative systems may include one or more implants of one ormore types deployed from outside the heart, along with one or moreimplants of one or more types deployed from inside the heart using ablood-vessel approach. Systems with a plurality of implants deployedfrom outside and/or inside the heart may benefit from any of a varietyof imaging techniques so that the implant systems effectively excludescar tissue and limit a size of one or more heart chamber.

Referring now to FIGS. 15A-15E, another related embodiment of adeployment system 150 and implant 152 can be understood, along with amethod for its deployment. Anchors 154, 156 and tension member 158 arepreloaded into an outer sheath 160 of delivery system 150. Outer sheath160 has a proximal end (not shown) and a distal end 162, with the distalend being configured for penetrating through tissues bordering a chamberof a heart, such as the left ventricular wall W and septum S. Along withor instead of a sharpened distal tip, distal end 162 of sheath 160 mayemploy an energy delivery structure such as an electrosurgical cauterysurface, a powered mechanical structure such as an automated punch orrotary cutter, an optical energy delivery structure such as a laserrefracting surface, or the like. Distal end 162 will also open to allowpassage of anchors 154, 156, with the tip optionally being passivelydeflected by the anchors, steerable or articulating to allow passage ofthe anchors, or the like. Distal tip 162 preferably has a curved shapewith sufficient rigidity to distally penetrate tissues and allowadequate motion for deployment of the anchors.

As illustrated in FIG. 15A, delivery system 150 may optionally puncturethe septum S, travel across the left ventricle to the free wall W andpuncture the free wall. A distal anchor 154 can then be deployed asillustrated in FIG. 15B by retracting outer sheath 160 proximally,and/or by distally advancing an inner sheath 164 or other body disposedwithin the outer sheath, either of which can act to push open the distaltip 162 and expel the distal anchor 154 from the delivery system 150. Astension member 158 is affixed to distal anchor 154 (see FIG. 15C), thecomponents of delivery system 150 can be retracted proximally from thefree wall W leaving the distal anchor 154 to engage and anchor againstthe distal surface of the left ventricular wall.

As described above, the distal anchor may optionally expand laterally byarticulation of arms or the like. Alternatively, as seen in FIGS. 15A-C,the anchor may increase in its lateral profile by rotation of anelongate structure from a narrow profile orientation to a larger profileorientation. Regardless, outer sheath 160 and other components of thedelivery system 150 may be retracted proximally from the leftventricular free wall W and proximal anchor 156 can be deployed so as toengage the septum S as can be understood with reference to FIGS. 15C and15D.

Once the anchors are positioned, tension may be applied between themembers by pulling proximally on a proximal extension of tension member158, and/or by pushing distally against an anchor stop 168 using aninner tubular body 166 of deployment system 150. Anchor stop 168 maycomprise a one-way ratchet mechanism, a latchable or lockable structureconfigured for being affixed to tension member 158, or the like. Tensionmember 158 may be trimmed flush to the anchor and/or anchor stop oncethe left ventricular wall W and septum S have been brought together withthe desired tension.

Optionally, the tension force applied to tension member 158 may bepredetermined or preset using a spring or other biasing structure,weights, or the like. The tensioning force may be selected to be greaterthan the tension experienced by the tension member 158 during systole,but less than the tension applied by the heart structures duringdiastole. As a result, the tension member 158 would move the anchors154, 156 towards each other selectively between pressure peaks in theleft ventricle. This will result in incremental ratcheting of the anchorlocations into engagement, avoiding excessive forces being appliedagainst the heart tissue. In other embodiments, surgical personnel maymanually or otherwise apply gradually increasing forces until thetissues begin to move towards each other, approximation forces may beenhanced during systole (manually or automatically) in response to anoutput signal from a blood pressure sensor, or a mechanism may inhibitthe application of tension forces in response to blood pressure peaks orthe like. Some further alternatives can be employed to selectivelyapproximate the tissues while pressures in the heart chamber aretemporarily reduced, including rapid pacing of the heart, occludingblood flow into the heart or heart chamber, and the like.

Optionally, distal end 162 of sheath 160 or some other distal structureof delivery system 150 may be configured to orient one or both ofanchors 154, 156 as they are deployed. The anchors may have throughholes that are positioned or oriented to preferentially orient theanchors in a desired alignment. Anchor geometry may be determined todistribute contact forces between the anchor and the tissue in adesirable distribution. If tension member 158 is not tensionedsufficiently to give tissue-to-tissue contact and/or sealing, and/or ifit is otherwise desirable, the anchor may include a sealing member toinhibit blood or other fluid leakage from the heart chamber.

Referring now to FIG. 16, treatments will often employ a pattern 170 ofanchors 172 (and their associated implants) to effectively exclude atleast a portion of infarcted tissue 174 from a remaining heart chamber176. The pattern 170 will effect an overall volumetric remodeling orreshaping of chamber 176 of heart H, typically by excluding a distendedvolume and/or circumference 178, with the excluded region of the heartoften having expanded gradually over time due to disease progression ofcongestive heart failure.

The amount of infarcted tissue to be excluded may be determined usingtechniques similar to those that have been developed for moreconventional congestive heart failure surgical therapies. For example,the determination of the desired remaining heart chamber volume andshape may employ aspects of that method used in determining the size ofthe Blue Egg™ heart treatment sizing tool, which is commerciallyavailable from Estech of San Ramon, Calif.

Calculation of a desired change in volumetric shape of a heart chambercan be understood with reference to FIGS. 19A and 19B. Circumferencereductions in centimeters may be calculated at each of a plurality ofdiscrete cross sections of the heart based on a number of factors,including the body surface area (BSA), the desired left ventricularend-diastolic volume (LVEDV), the location of the cross section alongthe long axis 180, the measured and desired end diastolic diameter, andthe like. Note that the overall desired volumetric shape of the treatedheart may be provided by calculating an appropriate change to one ormore of the heart chamber cross sections, and by determining appropriatesizes for the other cross sections from the location along the long axis180. The treated size of the previously calculated cross sections mayalso be used.

In an exemplary embodiment, the desired volumetric shape and/orpre-treatment volumetric shape may be based on a geometrical model of aportion of the heart. More specifically, the targeted ventricular shapeof the reconstructed volume is based on a model of a portion of the leftventricle (LV). That portion is modeled as a truncated prolate spheroidwith the long axis extending from the mitral valve to the LV apex andthe short axis measured perpendicular to that axis, also sometimesreferred to as the LV diameter. The truncated cap corresponds to 45% ofthe volume of the non-truncated version. The long axis of the truncatedmodel is 60% as long as the long axis of the non-truncated prolatespheroid. The maximum diameter is assumed to be 80% of the long axis(full distance from mitral valve to LV apex). The “original” shape ofthe prolate spheroid is quite elongated; the short axis is only 48% aslong as the long axis. This model of the target LV shape is used todetermine anchor positions, as described herein. The modeled LV portionmay comprise that which extends from adjacent the mitral valve to theapex, so that (for example) the outflow track of the left ventricle maynot be included in the model.

In general, the reduction of diameter and volume may be inferior to thebase of the papillary muscles so as to avoid interfering with thefunction of the papillary muscles or chordae. The short axis measurementto the apex may also be restored via this approach. Anchor locations andimplant deployment may be patterned so that the distance between anchorpairs of an implant is equivalent to the desired circumference reductionfor a given cross section. Suitable size reduction calculations andapproaches will often be based on patient body surface area, and willoften take into account the diameter of the left ventricle prior totreatment for each distance from the mitral annulus. The location andsize of scar to be excluded will also be identified and considered. Adesired volumetric shape for the treated chamber of the heart can bedefined by a desired diameter at each cross section along thelongitudinal axis so as to promote good heart function for the remainingcontractile myocardium. These size reduction considerations can be usedto generate appropriate radius reduction targets, and can also be usedto identify an appropriate reduction in the effective length of the leftventricle or other heart chamber. Suitable final target shapes willmaintain the appropriate proportions between the volume and radius,thereby creating proper wall tension without overstressing the diseasedor healthy tissue. Exemplary overall shapes may include circular crosssections with a longitudinal cross section that is substantiallyelliptical or parabolic, as illustrated in FIG. 19B.

Identifying appropriate anchor locations may be facilitated using atemplate as illustrated in FIGS. 17A and 17B, and/or using a distancemeasurement between candidate anchor points as schematically illustratedin FIGS. 18A-C. Details on the calculations of circumferentialreduction, as well as the use of curved bodies for identifyingappropriate anchor locations, can be understood with reference to FIGS.18A and 18B. First addressing the calculations graphically representedin these figures, a comparison of the pre-treatment effective diameter190 of a chamber of heart H at a given axial cross section to a desireddiameter 192 (so as to provide a desired volumetric shape to thischamber, for example) identifies a desired change in cross section Δd.The total linear length of circumferential tissue ΔC to be excluded fromthe chamber at the cross section can then be calculated from

ΔC=Δd×π

FIGS. 18B and 18C schematically illustrate the use of a curving elongatebody within the heart to visualize a separation distance between anchorpoints that will generate the desired reduction in diameter at a givencross section. An initial puncture may be made in either the septum S orfree wall W near an edge of scar tissue ST. From initial puncturelocation 194, a length of steerable or otherwise bent catheter 196 maybe fed into the heart chamber, with the length of the catheter bodyinside the chamber being equivalent to the amount of circumference thatis to be removed from that cross section. By bending the catheter bodywithin the left ventricle so that it has a curvature that issubstantially equivalent to the curvature of the chamber wall, thecatheter can be engaged against a measurably suitable target locationfor the other anchor. In other words, the length of catheter body 196within the chamber will be a mirror image of the length of chamber wall198 between anchor locations, allowing the change in circumference (andthus diameter) to be known.

The length of body within the chamber may be identified usingmeasurement indicia at the distal or proximal ends of catheter body 196,with distal indicia typically being radiopaque, echogenic, or otherwisehighly visible under remote imaging. Proximal measurement indicia may beread from the proximal end of the catheter body using an appropriatelength element of the delivery system, as can be understood withreference to FIG. 18C. Similar measurements and selected circumferencelength reductions at each of a plurality of other cross sections of thechamber will generate the desired volumetric shape for effective pumpingby the heart.

As noted above, a variety of alternative structures and methods may beused to temporarily reduce pressure within the heart so as to allowvolume reduction without imposing excessive trauma on the heart tissues.Along with occlusion of blood flow using a balloon catheter (asillustrated in FIGS. 10 and 13), the ventricle may be paced using apacing catheter 202 or the like at a rapid rate, so that the ventricledoes not effectively pressurize the blood (and hence impose tension onthe left ventricular tissues). Other templates may expand using astent-like structure or the like.

An additional structure and method for identifying appropriate anchorlocation for deploying one or more implants for excluding scar tissueand/or reshaping a chamber of the heart can be understood with referenceto FIG. 17A and 17B. In this embodiment, a template catheter 206supports a template 208 that is expandable in vivo. Template 208 isintroduced into a chamber of heart H, either through the septum, theapex, or mitral valve. Once template 206 is within the left ventricle,the template can be expanded against the surface of the ventricle inalignment with the infarcted scar tissue. In the embodiment illustratedhere, template 208 is radially expanded by unrolling the template fromaround the axis of the catheter body, with the template materialengaging the contractile heart tissue that is to remain bordering thechamber after treatment.

Template 208 includes indicia or targets that are visible under thedesired imaging modality to be used during treatment. For example, thetargets may be radiopaque, echogenic, easily visible under directimaging, or the like. Suitable targets may comprise contrast filledbladders, discrete radiopaque markers, or the like. The surgeon may thendirect the anchor delivery device through the septum as described above,using the targets to determine an appropriate anchor placement for thedistal anchor. Once anchors 212 are positioned and tension members 214are ready to reduce the chamber volume, template 208 can again be rolledup to a small profile configuration and removed from the chamber.

Once all anchors are placed, the tension members may be tensioned tobring the epicardial tissues together. Some or all of the tensionmembers may be tensioned simultaneously. In some embodiments, some orall of the tension members may be tensioned sequentially. In the eventthat one or more anchor placement is determined to be inappropriate, thetension member may be cut at the septal wall of the right ventricle, onthe outside of the free wall of the left ventricle, or the like.

While exemplary embodiments have been described in some detail forclarity of understanding and by way of example, a variety ofmodifications, adaptations, and changes will be obvious to those ofskill in the art. Hence, the scope of the invention is limited solely bythe appended claims.

1. A method for treating a heart, the method comprising: decreasing,during beating of the heart, a distance between a first locationbordering a chamber of the heart and a second location bordering thechamber of the heart, wherein the distance is selectively decreasedwhile a pressure within the chamber is temporarily reduced so as topermanently and safely reduce a volume of the chamber.
 2. The method ofclaim 1, wherein beating of the heart induces a systolic pressure, andwherein the distance between the first location and the second locationis selectively and permanently decreased while the pressure within thechamber is less than the systolic pressure.
 3. The method of claim 2,further comprising: coupling a first anchor with the first locationalong the chamber; coupling a second anchor with the second locationalong the chamber; approximating the first and second locations of thechamber by applying tension between the first anchor and the secondanchor that is sufficient to reduce the distance during diastolicpressure but is not sufficient to reduce the distance during thesystolic pressure.
 4. The method of claim 3, wherein the tension isapplied intermittently during beating of the heart by incrementallydecreasing between systolic pressure peaks, a length of a tension memberextending between a first anchor coupled to the first location and asecond anchor coupled to the second location.
 5. The method of claim 4,wherein beating of the heart induces a diastolic pressure, and whereinthe tension is selectively and intermittently applied when the pressurein the chamber is closer to the diastolic pressure than the systolicpressure, and wherein the tension is not increased during the systolicpressure peaks.
 6. The method of claim 2, further comprising inhibitingblood flow into the chamber so as to temporarily decrease pressurewithin the chamber, and selectively reducing the distance while thepressure is decreased.
 7. The method of claim 6, wherein the blood flowinto the chamber is inhibited by introducing a balloon catheter into ablood path flowing toward the chamber, and expanding a balloon of theballoon catheter so that the balloon inhibits the blood flow.
 8. Themethod of claim 3, further comprising pacing the heart so as to limitheart-induced pressure in the chamber.
 9. The method of claim 1, furthercomprising decreasing a plurality of laterally off-set separationdistances between a first plurality of anchors and a second plurality ofanchors, the first and second pluralities of anchors being coupled tothe heart, and wherein the decreasing of the separation distanceseffectively excludes scar tissue of the heart from the chamber so as tomitigate congestive heart failure (CHF) of the heart.
 10. The method ofclaim 9, wherein at least some of the separation distances are reducedsimultaneously.
 11. The method of claim 9, wherein at least some of theseparation distances are reduced sequentially.
 12. The method of claim1, wherein the treatment is performed in a minimally invasive manner.13. The method of claim 1, wherein the distance is decreased using aplurality of anchors that penetrate scar tissue of the heart.
 14. Themethod of claim 13, further comprising characterizing the scar tissue byapplying pacing signals adjacent candidate anchor locations so as toavoid penetrating viable contractile tissues with the anchors.
 15. Amethod for treating a diseased heart, the method comprising: reducing,in a first cross-section, a first size of a chamber of a heart byapproximation of a first anchor location toward a second anchorlocation, the anchor locations disposed near edges of a diseased tissuebordering the chamber; determining, for a second cross-section, a secondreduction in size of the chamber, the second reduction in size beingdetermined in response to: an offset between the first cross-section andthe second cross-section, and a magnitude of the first reduction incross-section of the chamber; and effecting the determined secondreduction in size of the chamber by deploying third and fourth anchorsinto tissues of the heart bordering the chamber, and by reducing alength of a tension member extending between the third and forthanchors.
 16. The method of claim 15, wherein the magnitude of the firstreduction in cross-section is identified from a length of a bodyextending between locations of the first anchor and the second anchor.17. The method of claim 16, wherein the chamber in the first crosssection has a first cross-section diameter defining a first curvature,wherein the body has an axis between the first anchor and the secondanchor, the axis having an axis curvature substantially corresponding tothe first curvature, the magnitude of the first reduction incross-section determined by measuring the length of the curving axisbetween the first anchor location and the second anchor location,approximation of the first and second anchors effecting a change fromthe first diameter to a first reduced diameter.
 18. The method of claim15, wherein a magnitude of the second reduction in cross-section isidentified from a length of a body extending between locations of thethird anchor and the fourth anchor.
 19. The method of claim 18, whereinthe chamber in the second cross section has a second cross-sectiondiameter defining a second curvature, wherein the body has an axisbetween the third anchor and the fourth anchor, the axis having an axiscurvature substantially corresponding to the second curvature, themagnitude of the second reduction in cross-section determined by thelength of the curving axis between the third anchor location and thefourth anchor location, approximation of the third and fourth anchorseffecting a change from the second diameter to a first reduced diameter.20. The method of claim 15, further comprising determining the secondreduction in size in response to a diseased size of the chamber in thesecond cross section before the second reduction.
 21. The method ofclaim 20, wherein the second reduction in size is determined bycomputing a change in length of a circumference of the second crosssection from a desired change in diameter of the second cross section.22. The method of claim 15, further comprising determining, for each ofa plurality of cross-sections, an associated desired reduction in sizeof the chamber, the associated reduction in size being determined inresponse to: a diseased size of the chamber in the cross-section beforethe associated reduction, an offset between the first cross-section andthe cross-section, and a magnitude of the first reduction, so as todefine a desired volumetric shape of the chamber; and effecting eachdetermined reduction in size of the chamber by deploying associatedanchors into tissues of the heart bordering the chamber, and by reducinga length of a tension member extending between the anchors to generatethe desired volumetric shape of the chamber.
 23. A method for treating adiseased heart, the method comprising: aligning an anchor patterntemplate with a chamber of the heart, the anchor pattern templateidentifying a plurality of anchor locations; deploying a plurality ofanchors into tissue of the heart per the aligned template; and applying,between associated anchors, tension so as to approximate tissue adjacentthe associated anchors and reduce an effective size of the chamber. 24.The method of claim 23, further comprising inserting the anchor patterntemplate into the chamber in a small-profile configuration and expandingthe anchor pattern template to a large-profile configuration within thechamber.
 25. The method of claim 23, wherein the anchor pattern templateis aligned with scar tissue of the heart, and wherein the desiredvolumetric shape excludes the scar tissue from the chamber.
 26. A systemfor treating a heart, the system comprising: a first anchor for couplingto a first location bordering a chamber of the heart; a second anchorfor coupling to a second location bordering the chamber of the heart; atension member coupling the first anchor with the second anchor, thetension member configured to be selectively shortened in situ from anelongate configuration to a shortened configuration; and a heart stresslimiting component configured to be operatively coupled to the heart tofacilitate selectively shortening of the tension member to reduce a sizeof the chamber while the heart is beating and pressure within thechamber is temporarily reduced.
 27. The system of claim 26, wherein thetension member in the shortened configuration provides a permanentdecrease in separation between the first anchor and the second anchor,and wherein the pressure component in configured to limit the pressurewithin the chamber to less than systolic pressure during the shortening.28. The system of claim 27, wherein the component generates a tensionforce in the tension member that is sufficient to appropriate thelocations between systolic pressure peaks, and wherein the tensionmember has a plurality of intermediate configurations so that thetension member can be shortened intermittently during beating of theheart by incrementally decreasing a length of a tension member extendingbetween the first anchor and the second anchor between the systolicpressure peaks.
 29. The system of claim 27, wherein the pressurecomponent comprises a balloon catheter having a balloon configured forexpanding within a blood path flowing toward the chamber so as totemporarily decrease pressure within the chamber.
 30. The system ofclaim 26, further comprising decreasing a plurality of associated anchorpairs and tension members, each tension member coupleable to theassociated anchors of the pair and being configured for selectivelydecreasing of separation distances between the anchors of the pair so asto effectively exclude a scar tissue of the heart from the chamber andmitigate congestive heart failure (CHF) of the heart.
 31. The system ofclaim 26, further comprising a minimally invasive catheter systemreleasably receiving the anchors and tension member for deployment inthe heart in a minimally invasive manner.
 32. The system of claim 26,wherein the pressure component comprises a pacing catheter.
 33. A systemfor treating a diseased heart, for use with: a first implant setincluding a first anchor for coupling to a first location bordering achamber of the heart, a second anchor for coupling to a second locationbordering the chamber of the heart, and a first tension member forcoupling the first anchor with the second anchor, the first implantsuitable for reducing, in a first cross-section, a first size of thechamber of the heart by approximation of the first anchor locationtoward the second anchor location; a second implant set including athird anchor for coupling to a third location bordering the chamber ofthe heart, a fourth anchor for coupling to a fourth location borderingthe chamber of the heart, and a second tension member for coupling thethird anchor with the fourth anchor, the second implant set suitable forreducing, in a second cross-section, a second size of the chamber of theheart by approximation of the third anchor location toward the fourthanchor location; the system comprising: a processor configured fordetermining, for the second cross-section, the second reduction in sizeof the chamber, the second reduction in size being determined inresponse to: an offset between the first cross-section and the secondcross-section, and a magnitude of the first reduction in cross-sectionof the chamber.
 34. The system of claim 33, further comprising the firstanchor set and the second anchor set.
 35. A system for diagnosing ortreating a diseased heart, a chamber of the heart having a diameterdefining a curvature between a first location and a second location, thesystem comprising: a body extendable from the first location to thesecond location, the body having an axis with an axis curvaturesubstantially corresponding to the curvature of the chamber so that acurving length of the body between the locations approximates acircumference of the wall between the locations.
 36. The system of claim35, further comprising a plurality of anchor pairs and associatedtension members for approximating heart tissues and a processorconfigured for determining, for a plurality of cross-sections, anassociated treatment of the chamber, the associated treatment comprisinga reduction in size and being determined in response to: a diseased sizeof the chamber in the cross section before the treatment, an offsetbetween the cross-sections, and a magnitude of a first reduction, so asto define a desired volumetric shape of the chamber.
 37. A device fortreating a diseased heart, the device for use with a plurality ofanchors, the device comprising an anchor pattern template for aligningwith a chamber of the heart, the anchor pattern template comprisingindicia identifying a plurality of anchor locations such that when theanchor pattern template is aligned with the chamber, the plurality ofanchors are deployed into tissue of the heart per the aligned indicia,and tension is applied between deployed anchors so as to approximate thetissue, an effective size of the chamber is reduced.
 38. The device ofclaim 37, wherein the anchor pattern template has a small profileconfiguration for insertion into the chamber, and wherein the anchorpattern template is expandable in situ to a large-profile configurationwithin the chamber for alignment of the anchors therewith.
 39. Thedevice of claim 37, the heart having scar tissue along the chamber,wherein the anchor pattern template is alignable with the scar tissue ofthe heart so that when the anchor are deployed per the indicia and thetissue is approximated a desired volumetric shape of the chamber isgenerated, the desired shape excluding the scar tissue from the chamber.